This invention relates to mechanical apparatus operable by solar energy and more particularly to a pumping apparatus that utilizes thermal energy from the sun to activate a vaporizable fluid in a closed loop system for driving a conventional well pump.
In rural underdeveloped areas where electrical power or other conventional forms of power are either unavailable or highly expensive there has long been a critical need for a workable, efficient apparatus operable by solar power and capable of pumping water for irrigation, stock watering and other uses. One previously disclosed solar powered pumping apparatus which attempted to fulfill these requirements is described in U.S. Pat. No. 3,937,599. It utilizes a solar panel that acts as an evaporator for a vaporizable fluid used in a remote motor unit having one chamber for vaporized gas and another chamber for the water being pumped. This system requires a well with a relatively large reception chamber for retaining a separate pump. In addition, a separate reservoir of water must be provided as a cooling sump and condenser for the working fluid. The relatively large number of components and their space consuming arrangement of such prior devices tended to make them functionally impractical, relatively expensive to manufacture as well as inefficient as a workable pumping apparatus and therefore not suitable for continuous, reliable operation in remote areas.
One particular problem in providing a satisfactory solar energy apparatus prior to the present invention related to the difficulty in developing a reliable and efficient pressurized vapor motor. To operate properly such a motor must allow a quantity of pressurized vapor to enter via inlet means and to be confined within an expansion chamber on one side of the piston. After the vapor has performed its work on the piston it must be removed via outlet means as a new quantity of gas enters. During these motor operation cycles the inlet and outlet means must be opened and closed with precision and proper timing and the expansion chamber outlet must be sealed as the pressurized vapor works on the piston. The present invention provides a motor with a built in valving system that is controlled in part by movement of the piston and overcomes the aforesaid problems.
It is therefore a general object of the present invention to provide an improved solar powered pumping apparatus and one that overcomes the disadvantages of prior art devices heretofore proposed.
Another object of the present invention is to provide a solar powered pumping apparatus that is relatively compact with all of its components combined in a unique manner on a single frame structure.
Yet another object of the present invention is to provide a solar powered pumping apparatus that is easy to install and also easy to service and maintain without special tools or skilled labor.
Another object of the present invention is to provide a solar powered pumping apparatus that utilizes a unique motor located within a solar collector so as to be operable at a high level of efficiency by solar heated vapor to produce a positive reciprocating action applied to a pivotal lever arm.
Another object of the present invention is to provide a solar powered pumping apparatus wherein vapor operated motor unit located within a solar collector is operably connected to a pivotal lever arm that in turn operates a fluid pump for condensed vapor.
Another object of the present invention is to provide a solar powered pumping apparatus wherein the water being pumped is utilized to condense the vapor that was previously used in the motor unit.
Still another object of the present invention is to provide an improved vapor pressure motor with its own valve control means for producing a continuously reciprocating action requiring no lubrication.
Another object of the invention is to provide a solar powered motor apparatus including a combination on-off and check valve that will assure self starting of the vapor pressure motor whenever the sun's rays fall upon the apparatus.
Yet another object of the invention is to provide a solar powered motor in combination with a well pump jack that is particularly well adapted for ease and economy of manufacture.